Hough-space silhouette algorithms
Geometric silhouettes are curves on surfaces that separate front-facing and back-facing regions for a given viewpoint. On polygon meshes, these silhouettes can conveniently be found and updated as the viewpoint moves by considering the polygons' supporting planes. To do this efficiently, we need a compact way to represent these planes. We have found that the geometric Hough transform produces a "well-behaved" data set, and lends itself to elegant algorithms for silhouette extraction and update.